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Stuck with Nth rarest element program

 
Greenhorn
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import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

public class NthRareElemnt {

public static void main(String args[]){

int arr[]={2,2,3,1,1,4,4,4,3,5};
ArrayList<Integer> lis = new ArrayList<Integer>();
for(int i :arr){
lis.add(i);
}
Set<Integer> se = new HashSet<Integer>(lis);
Map<Integer,Integer> m = new HashMap<Integer,Integer>();
   for(int temp:se){
   
    m.put(temp,Collections.frequency(lis,temp));
   }
   Set<Entry<Integer,Integer>> set = m.entrySet();
   ArrayList<Entry<Integer,Integer>> al = new ArrayList<Entry<Integer,Integer>>(set);
   Comparator<Entry<Integer,Integer>> c = new Comparator<Entry<Integer,Integer>>(){
public int compare(Entry<Integer, Integer> o1,Entry<Integer, Integer> o2) {
// TODO Auto-generated method stub
Integer i1 = o1.getValue();
Integer i2 = o2.getValue();
return i1.compareTo(i2);
}
   };
   Collections.sort(al, c);
   for(Entry<Integer,Integer> e: al){
    System.out.println(e.getKey()+ "----"+e.getValue());
   }
   
}

}


output :
5----1
2----2
1----2
3----2
4----3

(element -> frequency in sorted order)

I try to do the program like this .But i'm stuck after this . Could someone please help me to proceed further ?
 
Marshal
Posts: 8880
638
Mac OS X VI Editor BSD Java
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Welcome to the Ranch.

You said you stuck, but you didn't explain what stopped you.

One more thing. When you post code, don't forget to use code tags. Simply select the code snippet and hit the Code button in the text assembling panel.

An example how code would look like using code tags:

And compare with the version without the code tags, basically as you have:

public class Test {

   public static void main(String[] args) {
       System.out.println("Hello, World!");
   }
}

As you see former version is much better to read, understand and discuss (as it has line numbers and adds some colour coding).
 
Don't get me started about those stupid light bulbs.
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